/* Error handler for noninteractive utilities
   Copyright (C) 1990-1998, 2000, 2001, 2002 Free Software Foundation, Inc.
   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2, or (at your option)
   any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License along
   with this program; if not, write to the Free Software Foundation,
   Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */

/* Written by David MacKenzie <djm@gnu.ai.mit.edu>.  */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdarg.h>

#include "error.h"
#include "gettext.h"

#define VA_START(args, lastarg) va_start(args, lastarg)

/* If NULL, error will flush stdout, then print on stderr the program
   name, a colon and a space.  Otherwise, error will call this
   function without parameters instead.  */
void (*error_print_progname) ();

/* This variable is incremented each time `error' is called.  */
unsigned int error_message_count;

/* The calling program should define program_name and set it to the
   name of the executing program.  */
extern char *program_name;

static void print_errno_message (int errnum)
{
  fprintf (stderr, ": %s", strerror (errnum));
}

static void error_tail (int status, int errnum, const char* message, va_list args)
{
  vfprintf (stderr, message, args);
  va_end (args);

  ++error_message_count;
  if (errnum)
    print_errno_message (errnum);
  putc ('\n', stderr);
  fflush (stderr);
  if (status)
    exit (status);
}


/* Print the program name and error message MESSAGE, which is a printf-style
   format string with optional args.
   If ERRNUM is nonzero, print its corresponding system error message.
   Exit with status STATUS if it is nonzero.  */
/* VARARGS */
void error (int status, int errnum, const char *message, ...)
{
  va_list args;

  fflush (stdout);
  if (error_print_progname)
    (*error_print_progname) ();
  else
  {
	  fprintf (stderr, "%s: ", program_name);
  }

  VA_START (args, message);
  error_tail (status, errnum, message, args);
}

/* Sometimes we want to have at most one error per line.  This
   variable controls whether this mode is selected or not.  */
int error_one_per_line;

void error_at_line (int status, int errnum, const char *file_name,
	       unsigned int line_number, const char *message, ...)
{
  va_list args;

  if (error_one_per_line)
  {
    static const char *old_file_name;
    static unsigned int old_line_number;

    if (old_line_number == line_number && 
       (file_name == old_file_name || strcmp (old_file_name, file_name) == 0))
      /* Simply return and print nothing.  */
      return;

    old_file_name = file_name;
    old_line_number = line_number;
  }

  fflush (stdout);
  if (error_print_progname)
    (*error_print_progname) ();
  else
  {
	  fprintf (stderr, "%s:", program_name);
  }

  if (file_name != NULL)
  {
	  fprintf (stderr, "%s:%d: ", file_name, line_number);
  }

  VA_START (args, message);
  error_tail (status, errnum, message, args);
}
